You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <alllinks galcontinue="CPanel" />
  </query-continue>
  <query>
    <pages>
      <page pageid="156" ns="0" title="Backup &amp; Restore Databases - MS SQL" />
      <page pageid="940" ns="0" title="Billing - Contacts &amp; Sub-Accounts" />
      <page pageid="957" ns="0" title="Billing - Manage &amp; Pay Invoices" />
      <page pageid="948" ns="0" title="Billing - Manage Credit Card" />
      <page pageid="930" ns="0" title="Billing - Password Reset" />
      <page pageid="922" ns="0" title="Billing - Register Account" />
      <page pageid="944" ns="0" title="Billing - Security Question" />
      <page pageid="934" ns="0" title="Billing - Update Account Information" />
      <page pageid="961" ns="0" title="Billing - View Email History" />
      <page pageid="531" ns="0" title="CIDR notation" />
    </pages>
  </query>
</api>